Annealing of titanium - titanium nitride in contact hole
US5591672A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 27, 1995 |
| Grant date | Jan 7, 1997 |
| Priority date | — |
| Expiry date | Oct 27, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76877
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A process has been developed in which small diameter contact holes can be filled with chemically vapor deposited tungsten, without severe attack of the contact hole liner materials. An adhesive layer of titanium, and a barrier layer of titanium nitride are used for the contact hole liner, and are deposited prior to tungsten process. A process consisting of subjecting the barrier layer of titanium nitride to a rapid thermal anneal, in an ammonia ambient, results in enhanced barrier characteristics. The robust titanium nitride layer is now able to survive the tungsten deposition process, and attack form fluorine ions, produced during the decomposition of the tungsten source, tungsten hexafluoride.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.